A fresh breath of ozone

Jose Luis Lopez of Ozone International hooks up wiring to an ozone generator the company installed in a McDougall & Sons controlled atmosphere storage facility in Monitor. A few fruit companies in the region are converting their CA facilities to ozone systems to reduce spoilage and minimize use of chemicals in storage.

MONITOR — Some people say it smells like fresh rain or rich, upturned soil. Manufacturers say it could become an equally important element to the region’s fruit future.

Ozone made on the spot and pumped into fruit storehouses could revolutionize controlled-atmosphere storage in North Central Washington, say execs for a Bainbridge Island company that designs and installs ozone generators. The gas can slow ripening and inhibit growth of bacteria and fungi that can spoil fruit and cost packing houses big bucks.

Over the next six weeks, Ozone International (OI), which makes ozone systems for the food industry, will install 27 of its generators in warehouses of three prominent NCW fruit companies — McDougall & Sons in Monitor, Auvil Fruit in Orondo and Gebbers Farms in Brewster.

“The use of ozone has caught on in a big way,” said OI spokesman Mark Leader. “We see it as a major shift in controlled-atmosphere facilities as fruit companies search for safer, environmentally friendly ways to control spoilage and maintain fruit quality.”

Last week in an enclosed catwalk above an empty, three-story-high controlled-atmosphere unit, an OI crew put the finishing touches on the installation of two generators that will feed several storage units here at a McDougall & Sons shipping facility.

Cost of ozone installations vary by facility, but $20,000 to $40,000 per generating system is typical, said Alonso Lopez, OI’s installation manager. Crews spend about two days installing each system’s generator, control and analysis box, tubing and wiring.

To make ozone, a generator sucks in regular air and zaps it with an electrical charge. The oxygen (O2) in the air takes on an extra molecule to become O3, the same compound that trails after lightning storms. OI’s generators feed ozone into a storage unit at about 100 parts per billion.

The technology isn’t new. In the early 1990s, Gebbers Farms used ozone to retard spoilage for sliced-apple products. And a few years later the company expanded ozone testing at several facilities.

“We initially tested ozone in two controlled atmosphere rooms and found it greatly reduced mold and decay,” said Richard Thomason, a plant engineer at Gebbers. “Then we tried it in eight rooms and got the same results with our Galas (apples). They were firmer and had better flavor than the previously non-treated fruit.”

Today, Gebbers treats fruit with ozone in 20 controlled-atmosphere rooms and plans to add another 16 in the next month.

The difference now, said OI’s Mark Leader, is that the machinery has evolved to be more compact, more efficient, cheaper to operate, and cheaper and easier to install.

“In the long run, it also saves money for the fruit company,” said Lopez.

“Across the industry, fruit loss of 4 to 5 percent means a big job in repackaging stored fruit for market,” he said. “Studies are showing that ozone greatly reduces spoilage and can push repackaging to zero — no need to re-box the fruit when it leaves the storage unit.”

Packing house supervisors say ozone also reduces use of post-harvest chemicals needed to fight microorganisms — keeping fruit chemical-free for domestic and export markets — while maintaining the fruit’s taste, texture and smell.

“Now we use zero post-harvest fungicides,” said Walt Hough, treasurer of Auvil Fruit. “Ozone has been a giant chemical-free tool for us.”

Added Leader, “Some countries don’t accept fruit that contains chemicals. Ozone can help boost consumer confidence that they’re getting chemical-free fruit — both for exports and for markets right here at home.”

Reach Mike Irwin at 509-665-1179 or (javascript required to see email). Read his blog Everyday Business or follow him on Twitter at @MikeIrwinWW.